Marinate or season the chicken breasts and grill on both sides until cooked through, about 7 minutes on each side. Cooking time will vary depending on thickness of the chicken and temperature on the grill.
Meanwhile, in a mixing bowl, toss together the diced mango, the diced avocado and the diced red pepper with the vinaigrette.
Cook the rice as directed. Note that brown rice can take almost an hour to cook.
Serve the grilled chicken breasts over salad greens or rice, with the mango & avocado salsa on top.